Method of heat treating a cemented carbide material

A method of producing a tool comprising a substrate and a hard-face coating metallurgically bonded to the substrate, the method comprising the steps of:

• providing a steel substrate;
• providing a composition of fully sintered granulate grains;
• applying the fully sintered granulate grains onto the substrate;
• the resultant cemented carbide material on the steel substrate comprising at least 0.1 wt. % Si, at least 5 wt. % Cr, less than 5 wt. % Mn, less than 10 wt. % Mo, at least 30 wt. % W, and the balance of the cemented carbide material comprising C and an iron group metal, M, M being selected from any of Co, Ni or an alloy thereof, the cemented carbide material further comprising inclusions of a metastable phase, the metastable phase comprising M, Cr, Si, W, and C, the metastable phase having a nanohardness of at least 12 GPa and a Palmqvist fracture toughness of below 7 MPa m1/2;
• the method further comprising:
• subsequently heat treating the cemented carbide material and substrate at a temperature of at least 700° C. to at least partial decomposition of the metastable phase, thereby producing a tool with a substrate and a hard-face coating metallurgically bonded to the substrate.